Article

When a client asked Nelson landscape designer Richard Blaikie to give him a lawn that would seldom need mowing, it sparked an interest in grass substitutes.

"He was a scientist, with a different way of looking at things," says Richard. "I soon found other clients who were keen to put away their lawn mowers yet retain an area of restful green that could be walked on".

Richard has a strong interest in how people live and how their lives can be improved by making their environment more natural, so he started collecting and propogating mat-forming plants that could act as lawns and green mulches. He could see their potential for reducing work and increasing visual appeal, while at the same time cutting down on the use of noise polluting mowers, blow vacs and line trimmers.

He began trialling lawns of thyme varieties which have great scent: pratia, with little blue star-shaped flowers; and native acaenas, which are good for dry, gravelly areas, where their green or purple foliage looks amazing. In summer they have burr-like scarlet flowers.

Richard tried Dichondra repens (Mercury Bay Weed), a much touted lawn substitute in times gone by, but it was a little weak for his liking. So he made the inovative move of combining several species to create an intriguing mix of colour and texture. This proved a good way to use dichondra, planted with purple acaena and purple-green leptinella.

The biggest break-through came when Richard started growing New Zealand native seaside plant Selliera microphylla, which forms dense patches of small green foliage with a mown-grass appearance, and which needs the attention of a mower only once or twice a year. It will tolerate wet conditions, doesn't mind periods of dry, and copes well with moderate foot traffic.

In nature, this plant is often covered with salt water during periods of extra-high tides and it gets blasted by salt-laden storms, meaning it's extremelty salt tolerant and therefore a breeze to keep free of weeds. How come you might ask. Believe it or not, by scattering salt. Richard buys agricultural salt by the sack, and sprinkles it over the salleria when weeds reach 2-3cm tall. He wets the foliage first, then sprinkles on the salt using an extra-large salt shaker - a can with a holey lid. After the first application of salt, all that's needed is spot treatments when weeds reappear. So far he hasn't met a weed that isn't killed by salt. Even clover - which is sometimes hard to get rid of with conventional weed killers - is dispatched easily. Richard estimates that before long his nursery will be producing 90 per cent selleria as demand for it increases.
Richard's mainly installed no-mow lawns in small gardens, although a recent job saw him plant a large area of selleria in an amphitheatre in Nelson.

As with so many native plants, selleria shows variations in growth habit in the wild, and Richard makes a point of checking how it's performing in various locations. He's particularly impressed with the way it grows on the rocks by the blowholes at Punakaiki, where it's trampled by the feet of hundreds of tourists every day. It copes just as easily as when it's being washed over by waves when the tide is high.

Not that selleria is right for every situation. It's not completely cold-hardy, so if someone in Queenstown, for instance, wants a no-mow lawn, Richard recommends thymes and the little native Muchlenbeckia Oxillaris, which can be mown if it grows above a desired height. He says muehlenbeckia has been a success in a Nelson planting where it's a foreground to flaxes and hebes. It's walked on a lot there, so it's flattened, but still growing happily.

Lawn substitutes for shade are another matter. Richard uses several different plants for such situations, including Pratia angulata, which has pretty white flowers, and the handsome ground-hugging native fern Blechmum penna-marina, which grows 5-10cm tall and handles light foot traffic. This is also a good plant for walls and banks, able to tolerate both moist and dry situations, light shade, and sun too, provided the soil doesn't dry out. It's an especially attractive fern in spring when the pink-tinged new growth emerges.

Fragrance is something that's often asked for in a lawn substitute and something selleria doesn't possess. Thymes are an obvious choice for a lawn that releases fragrance when walked on, and Richard has several varieties that are suitable for areas with light foot traffic.
He also has customers who fondly remember the scent of pennyroyal and Corsican mint in their grand-parents' lawns (which, in the days before spraying became commonplace, included a mixture of plants) and want these plants incorporated into their own. Walking on or mowing such plants can be a heady experience, the crushing releasing voatile oils which waft into the air.

At Richard's nursery, seedlings for no-mow lawns are grown in trays. At planting time, they're tipped out and cut into plugs, according to the variety, and planted out. It usually takes three to six months for the plugs to meet up, he says, although selleria will soon be available as turf for instant effect. The plants become more dense as they age.

If you want a no-mow lawn, prepare soil as for a conventional lawn. It should be as weed free as possible, via herbicides and weed mats, but not too compacted.

Weed problems should be minimal once established. Watering needs depend on the species used; some require no watering at all, others just a little during dry spells. Watering does help while they're establishing, however.

You could try concocting your own mix using some of the plants listed here. While seed is rarely available for these mat-forming plants, seedlings can sometimes be found at garden centres or native nurseries, or else Richard sends no-mow plants nationwide.

Some of these plants are suitable for growing on walls too. Richard recently built a wall for a medical practice, which wanted a bold feature and to reduce noise. The combination of a thick wall of growing medium and dense plants really does dampen sound. Richard says the trick to is to place insulating walls as close to the source of the noise as possible. If road noise is the problem, the walls need to be on the road boundary, not near the dwelling.

"I've done some caveman-type trials with these walls, running a chainsaw full bore on one side while friends on the other have held a conversation at normal levels with ease", he says. However, he discovered that moving 20cm back with the chainsaw makes for high noise levels on the other side of the wall.

The main plants he uses on the walls are both natives: Muehlenbeckia axillaris and wahlenbergia. In shady aspects, he plants baby's tears, Soleirolia soleirolii. You can use greywater on such walls too, a great way to cut your water use.

Richard sometimes gets requests for plants to grow on roofs. Succulents are popular but they are brittle, so if your TV aerial needs fixing, the plants will be damaged. Selleria is a tougher option.

Weight is a problem for roof gardens, so Richard uses the soil-less mix he makes to use in sound-reducing walls. An ideal growing medium, it's made from shredded polystyrene, coconut fibre and fertiliser, is very lightweight and provides excellent insulation.